A soft magnetic alloy consists essentially of 5 percent by weight\u2266Co\u226630 percent by weight, 1 percent by weight\u2266Cr\u226620 percent by weight, 0. In one aspect, \u03b2-sheet mimetics are disclosed having utility as protease inhibitors in general and, more specifically, as serine protease inhibitors such as thrombin, elastase and Factor X inhibitors. A medical device providing a desired amount of retrograde fluid flow can be modified after permitting the medical device to remain in a body cavity for a remodeling-effective time period. Furthermore, an ordinary mode and the toner save mode are automatically switched or arbitrarily switched manually.